I don't recall reading that homosexuality carries a death sentence, I think it was something more along the lines of "God hates that, shunned by community, denied entrance to heaven etc" The point was that some people like to use the bible as an argument against homosexuality, claiming that it's God's law so it must be obeyed. But there are other laws in there that people are happy to ignore. There are better examples, this is just the only one I could remember

But this is getting off track from the original point and will eventually lead to a discussion over semantics. The King James bit sounds familiar, that could be my version. Which of course leads to an interesting point. How does one know which is the proper interpretation of the original? Mine sounds different from yours and you could probably discuss the same passage with polarised interpretations based on the wording of the passages in different Bible versions.

Out of curiousity, how many different versions of the bible are there and do they vary much?

Well, to use the Lord's name in vain, you must first use a name.
"God" isn't a name.
Note that in English, certain passages have LORD in all capital letters, like I just typed. That means the original word was God's name, YHWH or YHVH, which probably sounds like "Yahweh." Sometimes, it's "Elohim Yahweh," "Elohim" simply being the Hebrew word for "God." To use it in vain, means (like anything in vain) to use it without purpose or cause. It's true. Most Christians are just... ignorant. Even of their own faith. You'll find that those who assert you must follow laws to make it into heaven are also those who spend more time in the Old Testament than the New Testament. Coincindence? Well, I mentioned translation, not interpretation.
(Assuming you meant translation)... It's determined by determining the date of the manuscripts. The youngest ones are likely to be most authentic. They sound different because there is no such thing as a word-for-word translation. Even upon studying all English translations of the Bible in there entirety, you have learned all that it has in it's original languages. Take witchcraft, for example. English lacks appropriate words to describe different types. (Read Deuteronomy 18 to see what I mean. It's vague.) Studying it in Hebrew reveals more specifics, and we can also determine that all forms of witchcraft are not prohibited. Only those which can cause harm (like spoken curses), upset a balance (like fortune-telling), or those that involve the dead or ungodly spirits (communicating with the dead, necromancing, etc.).
That was a nice thing to learn, and I'd always suspected it.

I can tell more on that if anyone's interested. There's *lots* of different translations, there are only a few that vary, usually the older translations like the KJV. As far as I know, the newer translations use the earliest possible manuscript to translate from. I'm not sure where the manuscripts used to translate the KJV came from, but they're certainly not the originals.
It's not good to study in only one translation, because certain words in the original languages may have multiple meanings, and thus different translators will translate differently. Studying multiple versions allows us to get a general idea of what kind of word was originally used. Not as good as studying in Greek, Hebrew, or Aramic, but it's the next best thing.